US7891584B2 - Fuel injection valve - Google Patents

Fuel injection valve Download PDF

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Publication number
US7891584B2
US7891584B2 US11/911,515 US91151506A US7891584B2 US 7891584 B2 US7891584 B2 US 7891584B2 US 91151506 A US91151506 A US 91151506A US 7891584 B2 US7891584 B2 US 7891584B2
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Prior art keywords
injection valve
fuel injection
housing
guide sleeve
supporting body
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Expired - Fee Related, expires
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US11/911,515
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US20080210784A1 (en
Inventor
Marco Ganser
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Ganser Hydromag AG
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Ganser Hydromag AG
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Publication of US20080210784A1 publication Critical patent/US20080210784A1/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M63/00—Other fuel-injection apparatus having pertinent characteristics not provided for in groups F02M39/00 - F02M57/00 or F02M67/00; Details, component parts, or accessories of fuel-injection apparatus, not provided for in, or of interest apart from, the apparatus of groups F02M39/00 - F02M61/00 or F02M67/00; Combination of fuel pump with other devices, e.g. lubricating oil pump
    • F02M63/0012—Valves
    • F02M63/0014—Valves characterised by the valve actuating means
    • F02M63/0015—Valves characterised by the valve actuating means electrical, e.g. using solenoid
    • F02M63/0017—Valves characterised by the valve actuating means electrical, e.g. using solenoid using electromagnetic operating means
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M47/00—Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure
    • F02M47/02—Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure of accumulator-injector type, i.e. having fuel pressure of accumulator tending to open, and fuel pressure in other chamber tending to close, injection valves and having means for periodically releasing that closing pressure
    • F02M47/027—Electrically actuated valves draining the chamber to release the closing pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
    • F02M61/04—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00 having valves, e.g. having a plurality of valves in series
    • F02M61/10—Other injectors with elongated valve bodies, i.e. of needle-valve type
    • F02M61/12—Other injectors with elongated valve bodies, i.e. of needle-valve type characterised by the provision of guiding or centring means for valve bodies
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
    • F02M61/16—Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
    • F02M61/16—Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
    • F02M61/168—Assembling; Disassembling; Manufacturing; Adjusting
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
    • F02M61/16—Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
    • F02M61/18—Injection nozzles, e.g. having valve seats; Details of valve member seated ends, not otherwise provided for
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
    • F02M2200/16—Sealing of fuel injection apparatus not otherwise provided for
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
    • F02M2200/80—Fuel injection apparatus manufacture, repair or assembly
    • F02M2200/8076—Fuel injection apparatus manufacture, repair or assembly involving threaded members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M55/00—Fuel-injection apparatus characterised by their fuel conduits or their venting means; Arrangements of conduits between fuel tank and pump F02M37/00
    • F02M55/004—Joints; Sealings

Definitions

  • the present invention relates to a fuel injection valve for intermittent injection of fuel into the combustion space of an internal combustion engine.
  • a fuel injection valve is known, for example, from DE 10121340 A1. It has a housing body and a nozzle body pressed against said housing body at the end face in a sealing manner by means of cap nut. Said nozzle body defines a high-pressure space which is connected to a fuel high-pressure inlet arranged on the housing body and to an injection valve seat on the nozzle body. Located in the high-pressure space is a longitudinally adjustable injection valve member which interacts on the one side with the injection valve seat and defines on the other side, in the manner of a piston, a control space connected to the high-pressure space via a choke inlet.
  • control space is defined by a supporting body of groove-like design, in which the injection valve member engages and on which it is mounted in a sliding fit.
  • a closing spring is supported on the one side on the valve member and on the other side on the supporting body, which is held in contact with the housing body by the force of the spring.
  • a choke outlet runs through the supporting body from the control space, which choke outlet can be connected to and separated from a low-pressure outlet by means of an actuator-controlled pilot valve for the hydraulic control of the movement of the injection valve member.
  • a pilot valve member controlled by means of an actuator interacts with a pilot valve seat formed on the supporting body.
  • An object of the present invention is to provide a fuel injection valve which permits a short axial design of the nozzle body.
  • a fuel injection valve as claimed in claim 1 permits such a short axial design of the nozzle body by virtue of the fact that there is space for it together with a cap nut in a passage of a cylinder head of the internal combustion engine and yet it projects only slightly in a known manner beyond the cylinder head into the relevant combustion space.
  • an object of the present invention is to provide a fuel injection valve which can be produced in a simpler and more favorable manner.
  • the housing body has a recess open in the direction of the nozzle body and having a taper in the end region remote from the nozzle body.
  • the supporting body engages in the recess, where it is held in sealing contact with the taper by means of the closing spring.
  • This embodiment according to the invention permits reliable sealing of the high-pressure space between the housing body and the supporting body even when the taper and that part of the supporting body which interacts with the latter are ground.
  • simpler assembly is ensured by the supporting body being automatically centered on the taper.
  • the fuel injection valve according to the invention permits the arrangement of the taper deep in the housing body, since grinding in deep recesses is certainly possible, but lapping is no longer possible at acceptable cost.
  • Such deep recesses in the housing body permit a space-saving, in particular short, construction of the fuel injection valve and of the nozzle body. This is very advantageous when using the fuel injection valve in large diesel engines, such as, for example, marine or generator engines.
  • the supporting body has a conical end region whose cone angle is designed to be larger, but preferably only slightly larger, than the cone angle of the taper of the recess in the housing body, a very narrow sealing surface in the shape of a lateral surface of a truncated cone is achieved, as a result of which an especially reliable sealing effect is ensured. Since the sealing surface in this case comes to lie on a large radius of the cones, hydraulic forces acting in the lifting direction are minimized.
  • An outlet choke insert on which a pilot valve seat is formed can be made of an especially durable material, whereas a housing body can be made of another, cheaper material.
  • FIG. 1A shows, in longitudinal section, a fuel injection valve in which a supporting body is in contact with a housing body in a planar manner, an actuator arrangement is arranged in the housing body in an offset manner relative to an injection valve member, and said housing body accommodates an outlet choke insert on which a pilot valve seat of a pilot valve controlled by means of the actuator is integrally formed;
  • FIG. 1B shows a zoomed-in view of the fuel injection valve according to the embodiment shown in FIG. 1A ;
  • FIG. 2 shows, in longitudinal section, part of an injection valve according to the invention, having a recess which has a conical taper deep in the housing body, in which taper the supporting body engages by means of a conical end region;
  • FIG. 3 shows, likewise in longitudinal section, part of a second embodiment of the fuel injection valve according to the invention having an especially short overall length
  • FIG. 4 shows, in longitudinal section, part of a third embodiment of the fuel injection valve according to the invention in which the supporting body has an end region formed like a spherical cap and interacting with the conical taper in the housing body, and in which a guide sleeve for the injection valve member is integrally formed in one piece on the supporting body;
  • FIG. 5 shows, in longitudinal section, part of a fourth embodiment of the injection valve according to the invention in which the supporting body has a conical end region interacting with the conical taper, and the closing spring is supported on a guide piston which bears against the supporting body and engages in a cylinder-like section of the injection valve member;
  • FIG. 6 shows, in longitudinal section, part of a fifth embodiment of the injection valve according to the invention in which a cylindrical extension adjoins the conical end region of the supporting body, the pilot valve seat being formed on said cylindrical extension.
  • FIGS. 1A and 1B show a fuel injection valve 4 which is intended for intermittent injection of fuel into the combustion space 6 of an internal combustion engine 8 . It has an elongated housing 10 which has on the outside essentially the shape of a stepped circular cylinder and whose housing axis is designated by 12 .
  • the housing 10 consists of a one-piece housing body 14 , a one-piece intermediate body 15 and a one-piece nozzle body 16 .
  • the intermediate body 15 is held in sealing contact with an axial end face 20 of the housing body 14 by means of a clamping nut 18 screwed onto the housing body 14 and designed as a cap nut, whereas the nozzle body 16 is held in sealing contact with an axial end face of the intermediate body 15 by means of a cap nut 19 screwed onto the intermediate body 15 .
  • the intermediate body 15 and the nozzle body 16 define a high-pressure space 22 which extends from the end face 20 of the housing body 14 in the direction of the housing axis 12 up to a nozzle tip 24 of the nozzle body 16 , where an injection valve seat 26 in the shape of a lateral surface of a truncated cone is integrally formed on the nozzle body 16 .
  • the nozzle body 16 in a known manner, has nozzle openings 28 in the region of the nozzle tip 24 , the fuel being injected into the combustion space 6 through said nozzle openings 28 when the fuel injection valve is opened.
  • the high-pressure space 22 is connected to a fuel high-pressure inlet 32 at a free end face 20 ′ of the housing body 14 via a fuel feed channel 30 which runs in the intermediate body 15 obliquely to the housing axis 12 and through the housing body 14 parallel to the housing axis 12 and in such a way as to be offset relative to the latter.
  • the fuel high-pressure inlet 32 is connected in a known manner to a fuel feed, which feeds fuel under very high pressure of, for example, 1600 bar or higher to the fuel injection valve.
  • the fuel feed channel 30 opens in the intermediate body 15 into a circumferential-groove-like widened portion of the high-pressure space 22 .
  • a needle-shaped injection valve member 34 Located in the high-pressure space 22 concentrically to the housing axis 12 is a needle-shaped injection valve member 34 , which on the one hand interacts with the injection valve seat 26 and on the other hand, with a piston-like end region 36 , is guided like a double-acting piston in a guide sleeve 38 , forming a cylinder, in a close sliding fit of about 0.002-0.010 mm in such a way as to be displaceable in the direction of the housing axis 12 .
  • a closing spring 40 arranged concentrically around the injection valve member 34 is supported at one end in a known manner via a supporting disk 42 and a supporting collar 44 on an encircling shoulder of the injection valve member 34 and acts upon the latter with a closing force directed toward the injection valve seat 26 .
  • the closing spring 40 is supported on a first end face 46 of the guide sleeve 38 , which bears with its opposite second end face 46 ′ against a supporting body 48 .
  • the supporting body 48 of pill-like shape is held in sealing contact with the end face 20 of the housing body 14 by the force of the closing spring 40 .
  • the guide sleeve 38 Adjacent to the supporting body 48 , the guide sleeve 38 has radially projecting centering ribs 50 , by means of which it is held in a centered manner relative to the intermediate body 15 . Furthermore, the guide sleeve 38 , for its centering relative to the intermediate body 15 , has a guide ring 50 ′ which projects beyond the first end face 46 and encloses the end region on this side of the closing spring 40 in a centering manner.
  • centering ribs 50 and the centering ring 50 ′ are far apart in the axial direction and the piston-like end region 36 for guiding on the guide sleeve 38 is designed to be long in the direction of the housing axis 12 , direct guidance of the injection valve member 34 on the intermediate body 15 or nozzle body 16 can be dispensed with.
  • the guide sleeve 38 has radial passages 52 in the vicinity of the first end face 46 in order to connect said gap hydraulically with that part 22 ′ of the high-pressure space 22 which lies between the guide sleeve 38 and the injection valve seat 26 .
  • This ensures large cross sections of flow for feeding fuel from the fuel feed channel 30 through the gap between guide sleeve 38 and the intermediate body 15 , the radial passages 52 , the closing spring 40 and the gap between the supporting disk 42 and supporting collar 44 and the intermediate body 15 to the injection valve seat 26 .
  • said gap between the intermediate body 15 and the guide sleeve 38 ensures the fuel feed to fuel inlet channels 54 in the supporting body 48 .
  • the latter has a smaller outside diameter in a section adjoining the guide sleeve 38 than in a section facing the housing body 14 or alternatively has milled recessed portions. Said section facing the housing body 14 serves to center the supporting body 48 relative to the intermediate body 15 .
  • the fuel inlet channels 54 are formed by radial blind bores starting from the section having a smaller outer radius or from the milled recessed portions and by axial bores leading into said blind bores from the end face facing the injection valve seat 26 .
  • a choke bore 56 leads from the bottom of one of said blind bores into a section of a control channel 58 which is concentric to the housing axis 12 and runs through the supporting body 48 .
  • said guide sleeve 38 has a larger inside diameter in order to accommodate an intermediate valve body 62 such that it is movable by a small stroke in the direction of the housing axis 12 .
  • the intermediate valve body 62 interacts with an annular intermediate valve seat 64 which is formed on the supporting body 48 and into the region of which the fuel inlet channels 54 open out.
  • the intermediate valve body 62 closes the fuel inlet channels 54 .
  • the control channel 58 is connected to the high-pressure space 22 via the gap between the supporting body 48 and the intermediate valve body 62 and the fuel inlet channels 54 .
  • a further section of the control channel 58 runs concentrically to the housing axis 12 through the intermediate valve body 62 , said section being provided with a choke constriction 66 in its end region facing the injection valve seat 26 .
  • the intermediate valve body 62 is held in contact with the supporting body 48 by means of a spring 68 supported on the guide sleeve 38 .
  • That section of the control channel 58 which runs through the intermediate valve body 62 opens into a control space 70 , which is defined circumferentially by the guide sleeve 38 and axially by the injection valve member 34 on the one side and by the intermediate valve body 62 on the other side.
  • the housing body 14 has a blind-hole-like actuator-locating recess 72 which starts from the free end face 20 ′ and is offset relative to the housing axis 12 and lies opposite the fuel feed channel 30 .
  • a circular-cylindrical recessed portion 76 is incorporated in the housing body 14 coaxially to the substantially circular-cylindrical actuator-locating recess 72 .
  • a circular-cylindrical outlet choke insert 78 is inserted into said recessed portion 76 with circumferential clearance and is pressed in the direction of the actuator-locating recess 72 by means of a disk spring 80 supported on the housing body 14 .
  • a connecting section of the control channel 58 runs from the center of the axial end face 20 of the housing body 14 , obliquely relative to the housing axis 12 , to the bottom of the recessed portion 76 .
  • Running axially through the outlet choke insert 78 is a further section of the control channel 58 having an outlet choke constriction 82 in that end region of the outlet choke insert 78 which faces the actuator-locating recess 72 .
  • a known electromagnetic actuator 84 for controlling the fuel injection valve 10 via a pilot valve 86 is arranged in the actuator-locating recess 72 .
  • a pilot valve seat 88 integrally formed on that end face of the outlet choke insert 78 which faces the actuator 84 and running around the orifice of the control channel 58 interacts with a shank-like pilot valve member 90 .
  • the pilot valve member 90 is arranged in a continuous aperture of a sealing element 92 and is guided in a movable manner on the sealing element 92 in the axial direction by means of radially projecting ribs.
  • the sealing element 92 With an annular end-face sealing face, the sealing element 92 is in sealing contact both with the bottom 74 of the actuator-locating recess 72 and with the outlet choke insert 78 —radially outside the pilot valve seat 88 .
  • the force resulting in the sealing contact of the outlet choke insert 78 is ensured by the disk spring 80 and by that hydraulic force exerted by the fuel in the high-pressure space 22 .
  • the force for the sealing contact of the sealing element 92 with the bottom 74 is produced by a ring nut 94 which is screwed into the housing body 14 and which keeps the actuator 84 , in contact with the sealing element 92 on the other side, pressed in the direction of the bottom 74 .
  • the actuator 84 has an actuating shank 96 which interacts with the pilot valve member 90 and to which a plate-like armature 98 is fastened.
  • a plate-like armature 98 By electrical energizing of a coil 100 , the armature 98 and thus the actuating shank 96 are pulled against the force of an actuator spring 102 acting in the direction of the closed position of the pilot valve 86 , which leads to the opening of the pilot valve 86 .
  • the coil 100 is de-energized, the pilot valve 86 is closed by means of the actuator spring 102 .
  • the guide aperture for the pilot valve member 90 in the sealing element 92 is part of a low-pressure outlet channel 104 which extends through the sealing element 92 and the actuating shank 96 to a low-pressure space 106 accommodating the actuator spring 102 and from there through a radially through the housing of the actuator 84 and the housing body 14 to a low-pressure outlet, from which the fuel is returned into a fuel supply tank in a known manner.
  • the offset arrangement of the actuator 84 relative to the housing axis 12 and therefore relative to the injection valve member 34 and the offset arrangement of the fuel feed channel 30 permit an especially space-saving short embodiment of the fuel injection valve.
  • the intermediate body 15 has an annular supporting shoulder 107 , with which the clamping nut 18 is in sealing contact by means of a mating shoulder.
  • a free, flat, annular end face 18 ′ of the cap nut is designed as a sealing face.
  • this sealing face is in contact with a disk-shaped sealing ring 142 , for example made of copper, which in turn bears against a flat, annular mating sealing face 146 formed on a cylinder head 144 of the internal combustion engine 8 .
  • the housing body 14 is clamped against the cylinder head 144 in a generally known manner, for example by means of clamping screws, such that the intermediate body 15 , while interacting with the clamping nut 18 , the sealing ring 142 and the cylinder head 144 , seals off the combustion space 6 , defined by the latter and a cylinder of the internal combustion engine 8 , from the environment.
  • the nozzle body 16 together with the cap nut 19 in an injection valve passage 150 of the cylinder head 144 of normal size on the cylinder-space side of the end face 18 ′, designed as sealing face, of the clamping nut 18 and of the mating sealing face 146 .
  • the nozzle body 16 in a generally conventional manner, projects only slightly with its nozzle tip 24 beyond the cylinder head 144 into the combustion space 6 .
  • the nozzle body 16 of relatively very small design can be economically produced from a more wear-resistant and therefore substantially more expensive material than the remaining housing 10 , a factor which advantageously prolongs the service life of the fuel injection valve 4 .
  • a circular-cylindrical inner surface 19 ′ of the cap nut 19 has the function of aligning the nozzle body 16 with the housing axis 12 .
  • the nozzle body 16 is arranged in a sealing manner on the housing body 14 indirectly via the intermediate body 15 .
  • the cap nut 19 is at a small axial distance from the end face 18 ′, acting as sealing face, of the cap nut 18 .
  • the high-pressure space 22 extends into the housing body 14 through a recess 108 which is coaxial to the housing axis 12 and is open toward the intermediate body 15 and the sealing body 16 .
  • This recess 108 is provided with a conical taper 110 in the region of its bottom. From its tapered end remote from the high-pressure space 22 , the connecting section of the control channel 58 runs to the outlet choke insert 78 , which is again arranged offset.
  • a radial bore 112 which, as viewed in radial direction outside a short axial connecting bore to the recessed portion 76 , is sealed off from the environment by means of a pin 114 pressed into the bore 112 .
  • the bore 112 could also be arranged obliquely as in FIG. 1 .
  • the supporting body 48 with the fuel inlet channels 54 and the choke bore 56 has an extension 116 which engages in the taper 110 and is of conical design in an end region 118 interacting with the conical taper 110 .
  • the cone angle ⁇ of the conical end region 118 is designed to be slightly larger than the corresponding cone angle of the taper 110 . This results in a narrow sealing surface 120 (indicated by a broken line) in the direction of the housing axis 12 and in the shape of a lateral surface of a truncated cone.
  • This sealing surface 120 virtually in the form of a circular line lies at that end of the conical end region 118 which faces the high-pressure space 22 . Reliable sound sealing of the high-pressure space is achieved as a result.
  • the guide sleeve 38 accommodating the intermediate valve body 62 in the same way as in the embodiment shown in FIG. 1 and guiding the piston-like end region 36 of the injection valve member 34 in a cylinder-like manner, again has centering ribs 50 , but no longer has any centering ring 50 ′.
  • a cap-like annular disk 122 Put onto the first end face 46 of the guide sleeve 38 in order to center the closing spring 40 is a cap-like annular disk 122 , with which the end of the closing spring 40 on this side is in contact and from which an annular centering extension engages in the closing spring 40 .
  • the injection valve member 34 is guided on the intermediate body 15 by means of radially projecting guide ribs 124 in a region between the closing spring 40 and the end interacting with the injection valve seat 26 of the nozzle body 16 . Since the piston-like end region 36 of the injection valve member 34 is designed to be long in the axial direction relative to its diameter, a central arrangement of the guide sleeve 38 over its entire length is ensured. Finally, the guide sleeve 38 also no longer has any radial passages 52 , since fuel can now flow freely from the fuel feed channel 30 to the injection valve seat 26 .
  • the otherwise circular-cylindrical high-pressure space 22 is widened by an axially running groove 126 which is relieved on the intermediate body 15 and runs from that end of the latter which faces the housing body 14 up to approximately the middle of the closing spring 40 . Opening into this groove 126 is a radial groove 128 which forms a section of the fuel feed channel 30 and is connected to that section of the fuel feed channel 30 which runs parallel to the housing axis 12 through the housing body 14 .
  • the nozzle body 16 of small design is arranged in a sealing manner on the housing body 14 indirectly via the intermediate body 15 . There is space for about half the length of the intermediate body 15 together with the nozzle body 16 and the cap nut 19 in the injection valve passage 150 of the cylinder head 144 . The sealing is effected in the same manner as in the fuel injection valve 4 shown in FIG. 1 .
  • the nozzle body 16 is again designed to be short, but the housing body 14 is designed to be longer.
  • the intermediate body 15 according to FIGS. 1 and 2 is integrated in one piece in the housing body 14 .
  • Most of the high-pressure space 22 is located in the housing body 14 , and the recess 108 with the conical taper 110 at the end reaches correspondingly deeper into the housing body 14 .
  • the cap nut 19 is designed with a correspondingly smaller diameter and is screwed onto a stub of the housing body 14 .
  • the nozzle body 16 is arranged directly on the housing body 14 in a sealing manner and is fastened to the latter by means of the cap nut 19 —there is no clamping nut 18 .
  • the supporting body 48 with its conical end region 118 and the control channel 58 are designed in the same way as in the embodiment shown in FIG. 2 .
  • the guide sleeve 38 is again in sealing contact with the supporting body 48 by means of its second end face 46 ′. It has no centering ribs 50 (see FIGS. 1 and 2 ) but rather a centering ring 50 ′, as already shown in FIG. 1 , and therefore also radial passages 52 for the fuel.
  • the centering of the guide sleeve 38 at the supporting body 48 is effected during the fitting by the long embodiment, guided in the guide sleeve 38 in a close sliding fit, of the piston-like end region 36 of the injection valve member 34 , and the centering of the conical free end region of the injection valve member 34 is effected by interaction with the injection valve seat 26 of the nozzle body 16 .
  • the fuel feed channel 30 runs entirely in the housing body 14 , wherein it is formed by a blind-hole-like bore, parallel to the housing axis 12 but offset relative to the latter, and by a bore which opens into the blind-hole-like bore, runs at right angles to the housing axis 12 and is tightly closed relative to the environment by another pressed-in pin 114 ′.
  • the recess 108 defining the latter has a groove-like encircling widened portion.
  • the housing body 14 has, at a slight axial distance from the cap nut 19 , a shoulder-like, flat, annular sealing face 140 .
  • said sealing face 140 is in contact with the disk-shaped sealing ring 142 , for example made of copper, which in turn is in contact with the annular mating sealing face 146 formed on the cylinder head 144 .
  • the housing body 14 is clamped against the cylinder head 144 in a generally known manner, for example by means of clamping screws, such that, while interacting with the sealing ring 142 and the cylinder head 144 , it seals off the combustion space 6 , defined by the latter and the cylinder of the internal combustion engine 8 , from the environment.
  • the nozzle body 16 projects only slightly with its injection tip beyond the cylinder head 144 into the combustion space 6 .
  • the cap nut 19 for centering the nozzle body 16 , has the inner surface 19 ′, which, with a fit of typically 0.01-0.05 mm, interacts with the outer surface 16 ′ of the nozzle body 16 and an outer surface 14 ′ (corresponding to the outer surface 15 ′ of the intermediate body 15 ) of the housing body 14 .
  • the housing body 14 and the nozzle body 16 are designed in the same way as in the embodiment shown in FIG. 3 .
  • the supporting body 48 and the guide sleeve 38 in which the injection valve member 34 is guided with its piston-like end region 36 in a close sliding fit, are now designed in one piece.
  • the extension 116 of the supporting body 48 is formed with a spherical-cap-like end region 118 ′ which interacts in a sealing manner with the conical taper 110 of the recess 108 .
  • a reliable seal is achieved by achieving a sealing surface 120 which is very narrow in the axial direction and is virtually in the form of a circular line.
  • the guide sleeve 38 has no centering ribs 50 (cf. FIGS. 1 and 2 ), but rather a centering ring 50 ′, as known from FIGS. 1 and 3 .
  • a choke bore 56 which connects the control channel 58 and therefore the control space 70 to the high-pressure space 22 .
  • the sealing face of the housing body 14 is designated by 140 .
  • the closing spring 40 is located entirely in the recess 108 of the housing body 14 , and the supporting body 48 , the guide sleeve 38 , the injection valve member 34 and the closing spring 40 are fitted into said recess 108 from the side of the nozzle body 16 .
  • the housing 10 with the housing body 14 , having the sealing face 140 , and the nozzle body 16 is designed in a very similar manner to the embodiments shown in FIGS. 3 and 4 .
  • the recess 108 reaching deep into the housing body 14 is again provided with a conical taper 110 in its end region at the bottom.
  • the extension 116 having a conical end region 118 of the supporting body 48 again engages in said taper 110 , this extension 116 being designed in the same way as in the embodiments shown in FIGS. 2 and 3 .
  • the closing spring 40 is supported on one side on the free end of the injection valve member 34 , which is of cylindrical design in an end region 130 facing the closing spring 40 .
  • a guide piston 132 engages in this cylindrical end region with a close sliding fit of about 0.002-0.010 mm and defines, together with the cylindrical end region 130 of the injection valve member 34 , the control space 70 .
  • the guide piston 132 of one-piece design runs through the closing spring 40 , which is supported on a supporting shoulder 46 ′′ of the guide piston 132 with its end remote from the injection valve member 34 . With its second end face 46 ′, the guide piston 132 is in sealing contact with the supporting body 48 under the effect of the force of the closing spring 40 .
  • the guide piston 132 is kept centered in contact with the housing body 14 , a longitudinal groove 134 which runs parallel to the housing axis 12 ensuring the connection between the high-pressure space 22 and the fuel inlet channels 54 in the supporting body 48 .
  • a control passage 136 which is widened in a step-like manner in the end section 60 facing the supporting body 48 in order to accommodate an intermediate valve body 62 .
  • the latter in the same way as in the embodiments shown in FIGS. 1-3 , is again displaceable in the axial direction by a small stroke and, during hydraulic pressure balance, is held in contact with the supporting body 48 by means of the spring 68 supported on the guide piston 132 in order to close the fuel inlet channels 54 .
  • the intermediate valve body 62 has a stub engaging in the spring 68 , corresponding to a stub projecting from the piston-like end region 36 in the embodiments shown in FIGS. 1-3 .
  • the section of the control channel 58 having the choke constriction 66 again runs through the intermediate valve body 62 and its stub.
  • the control space 70 is connected to the high-pressure space 22 via the choke bore 56 when intermediate valve body 62 is in contact with the supporting body 48 .
  • the embodiment of the fuel injection valve shown in FIG. 6 is very similar to that in the embodiment shown in FIG. 3 .
  • the essential difference consists in the fact that the actuator 84 is arranged coaxially to the housing axis 12 .
  • the pilot valve seat 88 is integrally formed on an outlet choke extension 138 of the supporting body 48 . With its conical end region 118 , the supporting body 48 engages in the conical taper 110 of the recess 108 in the housing body 14 and is again in sealing contact with the latter.
  • the outlet choke extension 138 runs away from the conical end region 118 and is accommodated with radial clearance in the corresponding passage running from the taper 110 to the bottom 74 of the actuator-locating recess 72 .
  • the outlet choke constriction 82 is formed in the outlet choke extension 138 .
  • the pressure forces, caused by the high pressure in the recess 108 are completely absorbed by the seal between the conical end region 118 of the supporting body 48 and the taper 110 in the housing body 14 .
  • the element 92 ′ which in FIGS. 1 to 5 is designed as sealing element 92 , need not assume a function of either sealing or supporting the outlet choke extension 138 .
  • These provisions are dispensed with in FIG. 6 and consequently they need not be taken into account in the embodiment or during the assembly of the components involved.
  • the housing body 14 has the annular sealing face 140 for the sealing of the combustion space ( FIG. 3 ).
  • a common feature of all the exemplary embodiments shown in FIGS. 2-6 is the fact that the housing body 14 has a recess 108 open in the direction of the nozzle body 16 and having a conical taper 110 , and the supporting body 48 engages in this recess 108 and is held in sealing contact with the taper 110 by means of the closing spring 40 .
  • the nozzle body 16 is especially short, which permits a very compact embodiment of the fuel injection valve 10 .
  • the injection valve member 34 and the nozzle body 16 are readily aligned with the housing axis 12 , such that the injection valve seat 26 seals and the functioning is satisfactory during the opening and closing of the injection valve.
  • the clamping nut 18 could be formed with an inner surface and the housing body 14 and intermediate body 15 could be formed with corresponding outer surfaces in a similar manner to the surfaces 14 ′, 16 ′, 19 ′.
  • the effective centering is achieved with the surfaces 14 ′, 16 ′ and 19 ′.
  • FIGS. 1 , 2 , 3 , 5 and 6 function in a known manner as follows. Starting from the state which is shown in said figures and in which the pilot valve 86 is closed, the injection valve member 34 is in contact with the injection valve seat 26 and the intermediate body 62 is in contact with the supporting body 48 in such a way as to close the fuel inlet channels 54 . The same pressure as in the high-pressure space 22 prevails in the control space 70 and in the control channel 58 .
  • the actuator 84 is energized, as a result of which the pilot valve member 90 is lifted from the pilot valve seat 88 under the hydraulic force of the fuel and connects the control channel 58 through the outlet choke constriction 82 to the low-pressure outlet channel 104 .
  • the pressure in the control space 70 drops, as a result of which the injection valve member 34 is lifted from the injection valve seat 26 .
  • the intermediate valve body 62 remains in contact with the supporting body 48 .
  • the actuator 84 is de-energized, as a result of which the pilot valve 86 is closed.
  • the intermediate valve body 62 is lifted from its contact with the supporting body 48 , as a result of which the entire gap between the supporting body 48 and the intermediate valve body 62 is connected to the high-pressure space 22 by the fuel inlet channels 54 and the pressure in the control space 70 increases very rapidly. This in turn leads to a very rapid closing movement of the injection valve member 34 .
  • the pressure in the control space 70 then adapts itself to the pressure in the high-pressure space 22 , as a result of which the intermediate valve body 62 again comes into contact with the supporting body 48 under the force of the spring 68 .
  • the fuel injection valve is ready for the next injection of fuel.
  • the actuator 84 is energized, as a result of which the pilot valve member 90 is lifted from the pilot valve seat 88 under the hydraulic force of the fuel.
  • the control channel 58 is connected through the outlet choke constriction 82 to the low-pressure outlet channel 104 (see FIG. 1 ).
  • the pressure in the control space 70 drops, which leads to the lifting of the injection valve member 34 from the injection valve seat 26 .
  • Fuel is injected under high pressure through the nozzle openings 28 into the combustion space.
  • the actuator 84 is de-energized, as a result of which the pilot valve 86 is closed.
  • the pressure in the control space 70 increases, which causes a movement of the injection valve member 34 toward the injection valve seat 26 .
  • the injection operation is ended.
  • the intermediate body 15 can be formed in one piece with the nozzle body 16 .
  • This nozzle body 16 has a correspondingly larger axial length, such that it is in direct contact with the axial end face 20 of the housing body 14 . It is then held on the housing body 14 by the clamping nut 18 ; the cap nut 19 is dispensed with.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Electromagnetism (AREA)
  • Fluid Mechanics (AREA)
  • Fuel-Injection Apparatus (AREA)
US11/911,515 2005-04-14 2006-04-04 Fuel injection valve Expired - Fee Related US7891584B2 (en)

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
CH676/05 2005-04-14
CH6762005 2005-04-14
CH0676/05 2005-04-14
CH1115/05 2005-07-01
CH11152005 2005-07-01
PCT/CH2006/000191 WO2006108309A1 (fr) 2005-04-14 2006-04-04 Injecteur de carburant

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US20080210784A1 US20080210784A1 (en) 2008-09-04
US7891584B2 true US7891584B2 (en) 2011-02-22

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US11/911,515 Expired - Fee Related US7891584B2 (en) 2005-04-14 2006-04-04 Fuel injection valve

Country Status (6)

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US (1) US7891584B2 (fr)
EP (1) EP1869311B1 (fr)
AT (1) ATE447104T1 (fr)
BR (1) BRPI0608785A2 (fr)
DE (1) DE502006005245D1 (fr)
WO (1) WO2006108309A1 (fr)

Cited By (1)

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Publication number Priority date Publication date Assignee Title
US20130119161A1 (en) * 2010-08-09 2013-05-16 Robert Bosch Gmbh Injection device

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Publication number Priority date Publication date Assignee Title
JP5120655B2 (ja) 2005-07-18 2013-01-16 ガンサー−ハイドロマグ アーゲー 内燃機関用の蓄圧式噴射システム
US8544771B2 (en) * 2006-03-03 2013-10-01 Ganser-Hydromag Ag Fuel injection valve for internal combustion engines
DE102006029392A1 (de) * 2006-06-27 2008-01-03 Robert Bosch Gmbh Injektor
DE102006034112A1 (de) * 2006-07-24 2008-01-31 Robert Bosch Gmbh Kraftstoffinjektor
DE102007034034A1 (de) * 2007-07-20 2009-01-22 Robert Bosch Gmbh Injektor
US9803603B2 (en) 2013-03-01 2017-10-31 Ganser-Hydromag Ag Device for injecting fuel into the combustion chamber of an internal combustion engine
DE102016008836A1 (de) * 2016-07-20 2018-01-25 L'orange Gmbh Kraftstoffinjektor
US20220178335A1 (en) * 2019-04-15 2022-06-09 Cummins Inc. Fuel injector with radially orientable nozzle holes using splines

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EP0385397A2 (fr) 1989-02-28 1990-09-05 ELASIS SISTEMA RICERCA FIAT NEL MEZZOGIORNO Società Consortile per Azioni Injecteur électromagnétique de carburant pour moteur diesel
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US1762550A (en) * 1925-12-10 1930-06-10 Louis O French Internal-combustion engine
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DE513710C (de) 1929-08-02 1930-12-01 Motoren Werke Mannheim Ag Brennstoffeinspritzventil mit druckgesteuerter Nadel fuer kompressorlose Dieselmotoren
DE765232C (de) 1940-07-24 1954-08-16 Heinrich Lanz Ag Offene Brennstoffduese mit regulierbarem Zerstaeubungskegel
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DE10137890A1 (de) 2000-08-03 2002-06-20 Denso Corp Kraftstoffeinspritzvorrichtung
US20030141472A1 (en) 2001-01-05 2003-07-31 Patrick Mattes Injection valve
DE10121340A1 (de) 2001-05-02 2002-11-14 Bosch Gmbh Robert Common-Rail-Injektor
WO2004040119A1 (fr) 2002-10-31 2004-05-13 Robert Bosch Gmbh Soupape d'injection
WO2004099603A1 (fr) 2003-05-08 2004-11-18 Ganser-Hydromag Ag Soupape d'injection de carburant sans perte

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130119161A1 (en) * 2010-08-09 2013-05-16 Robert Bosch Gmbh Injection device
US9206779B2 (en) * 2010-08-09 2015-12-08 Robert Bosch Gmbh Injection device

Also Published As

Publication number Publication date
EP1869311A1 (fr) 2007-12-26
EP1869311B1 (fr) 2009-10-28
US20080210784A1 (en) 2008-09-04
DE502006005245D1 (de) 2009-12-10
BRPI0608785A2 (pt) 2010-01-26
ATE447104T1 (de) 2009-11-15
WO2006108309A1 (fr) 2006-10-19

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